1. Field of the Invention
The present invention relates to a method of manufacturing a liquid ejection head such as an ink jet recording head that ejects ink for recording.
2. Description of the Related Art
A liquid ejection head applied to a liquid jet recording system (for example, an ink jet recording system) typically includes a nozzle layer having minute ejection orifices and a liquid flow path. Multiple liquid ejection energy generating portions are included in a part of the liquid flow path. A method of manufacturing a liquid ejection head has been proposed, in which, by forming the nozzle layer of an inorganic material, the ejection orifices and the liquid flow path can be formed with high dimensional accuracy, and further, the liquid ejection head does not swell under the influence of moisture in liquid such as ink ejected from the ejection orifices.
In Japanese Patent Application Laid-Open No. 2000-225708, an ink jet recording head is proposed, having a structure in which Al is used as a material for forming an ink flow path pattern and an inorganic material such as SiO2 or SiN is used as a material for an orifice plate (nozzle layer) to form ink ejection orifices and an ink flow path. Further, in Japanese Patent Application Laid-Open No. 2000-225708, when an Al film that is the ink flow path pattern is removed, a method is used, in which etching is carried out using an etchant such as hydrochloric acid or phosphoric acid at room temperature.